Low voltage discharge lamp power supply

Abstract

A power supply for a gas discharge lamp has an oscillating circuit with two switches connected at a node in series and controlled by an oscillation ignition circuit having a diode that operates above a selected voltage threshold level. An energy storage circuit is connected to the node of the oscillating circuit switches and to the oscillation ignition circuit. It supplies energy to the oscillation ignition circuit and the oscillating circuit while voltage is momentarily below the selected voltage threshold level of the diode.

What is claimed is:  
     
       1. A power supply for a gas discharge lamp comprising an oscillating circuit having two switches communicating at a node in series controlled by an oscillating ignition circuit having a diode that operates above a selected voltage threshold level, and an energy storage circuit connected to said node and to said oscillation ignition circuit for supplying energy to said oscillation ignition circuit and said oscillating circuit while voltage across said diode is below said selected voltage threshold level of said diode, said lamp being coupled to said oscillating circuit node and across said energy storage circuit. 
     
     
       2. The power supply circuit of  claim 1  wherein said energy storage circuit comprises a capacitor connected on one side to said node of said oscillating circuit switches and to said oscillation ignition circuit through a second diode. 
     
     
       3. The power supply circuit of  claim 1  further comprising a rectifier connected to a source of alternating electrical current and communicating a rectified voltage to the energy storage circuit. 
     
     
       4. The power supply circuit of  claim 3  wherein said energy storage circuit comprises a capacitor connected on one side to said node of said oscillating circuit switches and to said oscillation ignition circuit through a second diode, whereby said energy storage circuit supplies energy while the voltage after rectification is lower than the voltage across the capacitor. 
     
     
       5. The power supply circuit of  claim 1  wherein said oscillating circuit is a push-pull, semi-bridged, self-oscillating circuit. 
     
     
       6. The power circuit of  claim 1  wherein the output voltage is high frequency 12 volts or less. 
     
     
       7. A power supply for a gas discharge lamp, comprising a push-pull, semi-bridged, self-oscillating circuit having two switches in series connected at a node and controlled by an oscillation ignition circuit having a diode that operates above a selected voltage threshold level, and an energy storage circuit connected to said diode and to said oscillation ignition circuit for supplying energy to said oscillation ignition circuit and said oscillating circuit while voltage across said diode is below said selected voltage threshold level of said diode, said energy storage circuit comprising a capacitor connected on one side to said oscillating circuit switches through a second diode and to said oscillation ignition circuit and said oscillating circuit through a third diode. 
     
     
       8. The power supply circuit of  claim 7  wherein the output voltage is high frequency, 12 volts or less. 
     
     
       9. A method of providing low voltage high frequency electric energy to a gas discharge lamp comprising the steps of: 
       (a) controlling an oscillating circuit having two switches connected at a node in series with an oscillation ignition circuit having a diode that operates above a selected voltage threshold level; and  
       (b) supplying energy to the oscillation ignition circuit and the oscillating circuit by an energy storage circuit connected to the node of the oscillating circuit switches and to the oscillation ignition circuit to power the oscillation ignition circuit and the oscillating circuit while the voltage across said diode is lower than the selected voltage across said diode threshold level of the diode.